This invention relates to a process for solidifying radioactive waste pellets.
Reduction of volume and solidification into drums of radioactive wastes generated in an atomic power plant are not only important for maximum utilization of a storage space in the plant site, but also indispensable for on-land storage as one of the ultimate disposals.
A process for reducing the volume of radioactive wastes by drying and pulverizing concentrated liquid waste containing Na.sub.2 SO.sub.4 as the major component and a slurry of ion exchange resin powder, major wastes generated in a BWR plant, thereby removing the water that takes the most portion of the volume of radioactive waste, and pelletizing the resulting powder has been so far investigated, and it has been confirmed that the volume can be reduced thereby to about one-eighth of the volume obtained according to the conventional process of direct solidification of the liquid waste and the slurry by cement. However, the said process has a good effect upon the reduction of volume, but still has such a disadvantage that a stable solidification product cannot be obtained by a hydraulic setting filler such as cement, etc., because cement is used, as mixed with water, and the water is reabsorbed into the dried powder to increase the volume of dried powder and break the pellets. To this end, a process for solidification by a filler requiring no water, for example, asphalt, plastics, etc. has been investigated. However, the process still has such disadvantages that operation must be carried out at a high temperature and the fillers themselves are expensive.
Thus, a process for solidification of radioactive waste pellets by a solidifying agent with easy operation and prolonged stability at a low cost has been desired.